Cooler water welling up along the coast of South America and moving west suggests the start of La Niña in the Pacific Ocean.

By Bob Berwyn

The shift from a powerful El Niño to the cooler La Niña phase of Pacific Ocean temperatures will temporarily end the planet’s recent record streak of record-warm years, according to climate scientists who see the cyclical ocean changes as a key factor in the long-term global climate change equation.

If climate change intensifies El Niño and La Niña, it could have big impacts on coastal erosion. @bberwyn photo.

Coastal Pacific areas seen as vulnerable to intensifying storms

Staff Report

If global warming strengthens the cycle of El Niño and La Niña events — as projected by some studies — it could lead to an increase in storm events bringing extreme coastal flooding and erosion in populated regions across the Pacific Ocean, according to a multi-agency study published today in Nature Geoscience.

“This study significantly advances the scientific knowledge of the impacts of El Niño and La Niña,” said Patrick Barnard, USGS coastal geologist and the lead author of the study. “Understanding the effects of severe storms fueled by El Niño or La Niña helps coastal managers prepare communities for the expected erosion and flooding associated with this climate cycle.” Continue reading “Study eyes coastal impacts of El Niño cycles”→

Does La Niña increase the odds of tornadoes?Study finds links between ENSO and tornado frequency in the Southern U.S. Photo courtesy NOAA.

Staff Report

FRISCO — Teasing out a link between large-scale atmospheric patterns and specific weather events isn’t easy against the backdrop of natural variability.

But a new study of the El Niño-La Niña cycle in the Pacific Ocean suggests that La Niña — the cool phase of the cycle — increases the frequency of tornadoes and hail storms in some of the most susceptible regions of the United States.

During La Niña, both vertical wind shear and surface warmth and moisture increase significantly in the southern states, making conditions favorable to severe storm occurrence.

‘It’s possible that anthropogenic climate change may once again be pushing these reefs towards another regional collapse …’

Staff Report

FRISCO — Past climate shifts resulting in La Niña-like conditions off the coast of Panamá resulted in a 2,500-year shutdown in coral reef growth, scientists said this week, warning that human-caused global warming could lead to similar conditions in the coming decades.

“We are in the midst of a major environmental change that will continue to stress corals over the coming decades, so the lesson from this study is that there are these systems such as coral reefs that are sensitive to environmental change and can go through this kind of wholesale collapse in response to these environmental changes,” said Kim Cobb, an associate professor in the School of Earth and Atmospheric Sciences at the Georgia Institute of Technology. Continue reading “More climate clues from ancient corals”→

FRISCO — Global warming could increase the frequency of extreme La Niña events in the Pacific Ocean, with more droughts in southwestern United States, floods in the western Pacific regions and increased Atlantic hurricane activity.

FRISCO — Drought conditions may persist across the southwestern U.S. this winter and may redevelop across the Southeast, according to the seasonal outlook from NOAA’s Climate Prediction Center.

“Even though we don’t have La Niña, the atmosphere across the Pacific seems to be stuck in a La Niña mode … It’s been quite surprising to us, how persistent the pattern is,” said Mike Halpert, acting director of the Climate Prediction Center.